Acetone Test Finish for PLA 3D Prints

January 22, 2013

After not being able to find much insights about using Acetone as a finish for PLA 3D Prints, just decided to get a bottle of the stuff anyway and see what it can really do.

Warning here though, Acetone is poisonous and highly flammable with a flash point of 17 Degrees C, so whenever you’re using it, please do so in a well ventilated space away from open flames (which may ignite the vapors in the air). And of course, don’t drink this stuff!

Basically scavenged a few 3D Printed PLA parts, some wire to hold the parts in the drip and Acetone. Later, you’ll see a larger glass bottle come into picture as the original plan to dip the picees directly into the Acetone bottle was foiled by the bottle’s narrow neck.

Here, I’ve used a large chicken essence glass bottle and wrapped the wire around the piece to be dipped. Obviously glass bottles should be used her since the Acetone melts plastics.

Wrapped the other end of the wire around a stick and used it to eyball the “depth” of the piece into the bottle, This helps to make sure the whole piece is submerged.

Let the timed tests begin!

After just the second dip, the Acetone started to turn visibly murky yellow, meaning some of the plastic has probably melted into the Acetone.

A view from the top of the dip.

And here are the results of 4 dips – ranging from 1 min 20 seconds to 20 seconds, 5 seconds and just a “dip”. Basically every single piece reacted with the Acetone to varying degrees and “melted”, turning white in the process. The piece left in the Acetone for the longest turned almost totally white and had a melted look. Even the last piece which was just dipped for a second or two turned white at several corners.

The conclusion is – Acetone is probably not a great way to finish 3D printed PLA part, although others have gotten great results with this method with ABS (which we would probably want to experiment with next when we get our ABS 3D Printer.) However, the silver lining in this – we now know how to create weathered effects for models which will be finished with a coat of spray paint, so the melted effect is one for our methods book. =)

This is late and therefore probably buried, but have you considered heating the acetone (carefully) and just exposing the plastic to the vapor? It might limit the amount of reaction that takes place and avoid the whitening.

Actually that’s a good idea which we haven’t tried but the thing is, with PLA, the acetone doesn’t seem to melt it at all, just turns it white which is why’s not all the hopeful. This is as compared to ABS where it really does dissolve in actone proper. 🙂